Overview
Almost every custom molder sends testing out. A sample goes to an independent laboratory, a queue absorbs it, and a report comes back a week or three later. If the result is good, the program continues. If not, the loop starts over and costs another week. That is normal in this industry, and most engineers have stopped noticing it.
Corry Rubber does not work that way. Our ISO/IEC 17025:2017 accredited laboratory is inside the building that molds the part, a short walk from the one that mixes the compound, staffed by our own technicians, running against the same schedule as production. The consequences are practical rather than philosophical.
A compound developed in the lab is run at volume by the same company
When a formulation is adjusted, the batch is mixed on our floor and aged in our lab. Development iterations that are weeks apart elsewhere are days apart here, which changes what is worth trying. On the sterilizer seal program, that loop is what made it feasible to develop and verify a non-fluorinated candidate against an incumbent fluoroelastomer at all.
It also removes the handoff. A compound qualified in an outside lab still has to survive being molded somewhere else, on different equipment, by people who were not part of the development. Here the presses that will run production are the presses that molded the test parts.
Acceptance testing on parts that came from overseas
Reshoring a legacy part usually means inheriting one without a specification. There is a print, a sample, and an assumption about what the rubber is. Before quoting, we characterize the incumbent part: durometer to ASTM D2240, tensile and elongation to ASTM D412, compression set to ASTM D395, heat aging to ASTM D573, and behavior in the actual service fluid to ASTM D471. That produces a real property window to build against, rather than a guess dressed up as a datasheet.
The same testing works as an acceptance gate. If overseas parts are still arriving while a transition is underway, we test them on receipt against the window the qualified part meets. Problems get caught at the dock instead of on the line.
That is not hypothetical. Our own testing has flagged overseas parts that did not comply with the ASTM standards called out on the customer's print, which is the kind of thing nobody finds until either a lab looks or the part fails in service.
Verification that does not depend on a supplier's word
Accreditation is the difference between a supplier stating a result and a supplier being audited on the method that produced it. Our scope lists each method, the property it measures, and the standard it follows, and it is public. When we report a compression set value, the method behind it has been assessed by an accreditation body rather than described in an email.
For regulated programs, that matters more than speed. The documentation is generated in the same place as the parts, so lot traceability, test records, and certificates of analysis are one chain rather than three companies' worth of paperwork stitched together.
What this does not mean
We are not an independent testing house, and for some purposes you should use one. An independent lab gives you third-party impartiality. Where a customer or a regulator requires that, use one. We are also not an analytical chemistry laboratory: trace-level composition work goes to specialists.
What we are is a molder that can answer a physical-property question about your part this week, to an accredited method, without leaving the building.